Tutorial 03. Exercise 1: CSC111 Computer Programming I

Transcription

1 College of Computer and Information Sciences CSC111 Computer Programming I Exercise 1: Tutorial 03 Input & Output Operators Expressions A. Show the result of the following code: 1.System.out.println(2 * (5 / / 2)); 2.System.out.println(2 * 5 / * 5 / 2); 3.System.out.println(2 * (5 / 2)); 4.System.out.println(2 * 5 / 2); B. Are the following statements correct? If so, show the output. 1. System.out.println("25 / 4 is " + 25 / 4); 2. System.out.println("25 / 4.0 is " + 25 / 4.0); 3. System.out.println("3 + 2 is " ); 4. System.out.println("3 + 2 is " + (3 + 2)); 5. System.out.println("3 * 2 / 4 is " + 3 * 2 / 4); 6. System.out.println("3.0 * 2 / 4 is " * 2 / 4); C. Suppose m and r are integers. Write a Java expression for mr2 to obtain a floating point result. D. How would you write the following arithmetic expression in Java? (r+34) 9 (a c) 3+d(2+a) a+bd t 5.5 (r + 2.5) E. Show the output of the following code: double a = 6.5; a += a + 1; a = 6; a /= 2; F. Show the output of the following code: int a = 6; int b = a++; System.out.println(b); a = 6; b = ++a; System.out.println(b); G. Is the following code going to print 0.1 and why? System.out.println( );

2 Exercise 2: Choose the correct answer: A. The value of 15 / 2 is: (i) (ii).5 (iii) ½ (iv) 0.5 (v) none B. The value of 18 / 3 is: (i) 6 (ii) 0.16 (iii) 6.0(iv) none C. The value of 22 % is: (i) 3 (ii) 1 (iii) (iv) 22/ D. The value of 5 % is: (i) 0 (ii) 2 (iii) 5 (iv) undefined E. The value of 1.0 / 4 is: (i) 4 (ii) 4.25 (iii) 4.0(iv) undefined F. The value of is: (i) 0 (ii) 0.0 (iii) 4 (iv) 4.0 G. The value of 5 * is: (i) 2 (ii) 5 (iii) 6 (iv) none Exercise 3 What are the values of x, y, z and w after running all statements? int x=5, y, z=3, w; y = x z; z = 2 * y + 3; w = x 2 * y + z; z = w x; w++; Exercise 4 Evaluate the following expressions: A * 6 / 8 2 B * 6 / 4 3 C * 6 / 4 3 D. int x=2, y=4; double z=.0, w=12.0; a. x * w + z y; b. x > w c. (x>y) (z<w) d.!(x>w) && (z==w) 1

3 Exercise 5 Write a program that changes a given amount of money into smaller monetary units. The program lets the user enter an amount as a double value representing a total in Riyals and Halals, and outputs a report listing the monetary equivalent in the maximum number of riyals, halfs (SR 0.5), quarters (SR 0.25), qirsh (SR 0.5), and halalah (SR 0.01), in this order, to result in the minimum number of coins. Here is a sampler un: Enter an amount, for example, 11.88: Your amount consists of 11 riyals 1 halfs 1 quarters 2 qirshs 3 halalahs 2

4 Tutorial 03 Solutions Exercise 1: A B / 4 is / 4.0 is is is * 2 / 4 is * 2 / 4 is 1.5 C. m * Math(r, 2) D. E. F / (3 * (r + 34)) 9 *(a+b*c)+(3+d*(2+a))/(a+b*d) * Math.pow(r + 2.5, t) G. No. double and float in java use rounding in expressing floating point numbers. Exercise 2: Exercise 3: x = 5 y = 2 z = 3 w = 9 Exercise 4: A. (i) B. (i) C. (ii) D. (iii) E. (ii) F. (iv) G. (i) A. (i) B. (i) C. (ii) D a. 2.5 D b. false D c. true D d. false 3

5 Exercise 5: Here are the steps in developing the program: A. Prompt the user to enter the amount as a decimal number, such as B. Convert the amount (e.g., 11.88) into halalas (1188). C. Divide the halalas by 100 to find the number of riyals. Obtain the remaining halalas using the halalas remainder 100. D. Divide the remaining halalas by 50 to find the number of halfs. E. Divide the remaining halalas by 25 to find the number of quarters. F. Divide the remaining halalas by 5 to find the number of qirshs. G. The remaining halalas are the halalas (can not be divided). H. Display the result. import java.util.scanner; public class ComputeChange { public static void main(string[] args) { // Create a Scanner Scanner input = new Scanner(System.in); // Receive the amount System.out.print("Enter an amount in double, for example 11.88: "); double amount = input.nextdouble(); int remainingamount = (int) (amount * 100); // Find the number of one riyals int numberofoneriyals = remainingamount / 100; remainingamount = remainingamount % 100; // Find the number of halfs in the remaining amount int numberofhalfs = remainingamount / 50; remainingamount = remainingamount % 50; // Find the number of quarters in the remaining amount int numberofquarters = remainingamount / 25; remainingamount = remainingamount % 25; // Find the number of qirshs in the remaining amount int numberofqirshs = remainingamount / 5; remainingamount = remainingamount % 5; // Find the number of halalas in the remaining amount int numberofhalalas = remainingamount; // Display results System.out.println("Your amount " + amount + " consists of"); System.out.println(" " + numberofoneriyals + " riyals"); System.out.println(" " + numberofhalfs + " halfs "); System.out.println(" " + numberofquarters + " quarters"); System.out.println(" " + numberofqirshs + " qirshs"); System.out.println(" " + numberofhalalas + " halalas"); } } 4